Check-valve.



C. J. DRURY.

Patented Oct. 19,1909.

/e 2. 4 7 Y m /NvflvTo/f @lli/aba Br @www A w/mfsses .UNITED VsfrnrnsPATENT OFFICE.

cnAnLEs J. nanny, or La JUNTA, eoLoaAno.

CHECK-VALVE.

To all whom 'it may concern:

Be litknown that I, CHARLES J. DnunY, of La Junta, in the county. ofOtero and Staf/e of Colorado, have invented a new and useful Improvementin Check-Valves, and do hereby declare that the following is a full andexact description thereof.

The object of my invention is to' provide a check valve which isespecially designed for use in the injector. inlets of boilers, althoughit is capable of application to various other devices. In the past,great diicult-y has been encountered in obtaining a checkjvalve of thisnature that was thoroughly satisfactory. The check valves that have beenin use become readily stuck through the interference of particles offoreign lmatter of different kinds, such as bolt heads, solid impuritiesin the water, parti-- cles of rubber, etc. When this has occurred,

it. has almost invariably been found necessary, owing to theinaccessibility of the parts of the check valve, to allow the steam toescape from the boiler, to remove the water,

and overhaul the l-boiler generally; and in' the case of locomotives ithas been found necessary to return the engine tothe round house andoverhaul the boiler in the same Y 1 v he check valve, which is anembodiment of my invention, has been designed to avoid all of thesediliculties. In general, it is a double .check valve. The lower one ofthe valves, the valves being so constructed that they operateindependently of each other, is smaller in diameter than the upper oneof the valves, and has a very .much smaller throw or lift than the uppervalve. In fact, the throw or lift of the upper valve is preferably,although not4 necessarily, exactly twice as great as that of the lowervalve.` In a construction of this kind it will be readily seen that anyforeign particles that might get into the injector pipe might,.by somepossibility, stick the lower valve, and retain it in .an inoperativeposition. Under these circumstances, however, the check valve wouldcontinue to operate perfectly, owin to the fact that the upper checkvalve woulv effectively retain the boiler pressure until the lower checkvalve could be` repaired..

` slieemqatmn of Letters Patent. Application me :ruy 2o, 190s. serialNo. 444,417.

interval is Patented oet. 19, 1909.

larger than the corresponding opening for the lower check valve. Again,owing to this arl-an ement, should any hard particle scratc the lowervalve and then pass through, this particle would readily pass beyond theupper valve into the boiler without scratching it. In such an event, theupper valve would continue to work perfect and retain the boilerpressure, while the lower valve could be detached and repaired, as aboveindicated.

Furthermore, one of the main features of my invention is to provide avalve structure comprising two independently operable superimposedvalves, having an intermediate web with more or less restrictedopenings. The purpose of this construction is to prevent anyl brokenparts of the lower valve,-

should the lower valve become broken, from reaching the upper valve andsticking it.

In the accompanying drawings F1gure 1 is a vertical section of a valveand valve casing, located in an injector pipe, which is connected to aboiler; and Fig. 2 is a horizontal section taken through the valvecasing, looking down upon the web.

v 1 re resents a fragment of a steam boiler,

to whlch is connected a right-angled coupling 2 by means of bolts. Thisright angled coupling 2 has located in its top a screw cap 4, havingdepending from its bottom a stop 5. A valve 6 is located within thecoupling 2. The upper part of the valve is provided with a stem 7 whichis adapted at times to contact with 4the stop 5.

Screw threaded into the bottom ofthe right angled coupling 2 is a pipesection 8', which haslocated on its top a valve seat 9 for the valve 6.The lower part of the pipe section8 is screw threaded at 10 to receivean interiorly screw threaded pipe coupling 11, constituting a valvecasing for the lower valve 12, which is smaller in diameter than valve.6. This pipe coupling 11 is provided with a valve Aseat 13 for thevalve 12. A web 11,4 is `fxedly secured inthe pipe section 8 immediatelyabove the valve 12, but separated therefrom by a suitable interval. Thisreferably exactly one-half of the distance etween the stem 7 of thevalve6 and stop 5 therefor, although this eXact relation I do not consideressential. The

.lower part of the pipe coupling 11 is exscrew thread 10 on the (pipesection 8, and the exterior screw threa on the pipe coupling 11 areexactly the same size, so that in case of injury tothe lower valve, o rthreads on valve cage the valve and the lpipe cou ling containing avalve seat therefor, mig t be entirely discarded for the time being andthe injector' pipe 15 coupled directly to the pipe section In theoperation of the device, should any solid particle succeed in stickingthe lower valve, the upper valve would continue to operate successfullyto retain the boiler pressure until the particle could be Yremoved fromthe lower valve. If, however, such a particle should pass the lowervalve, it could, of course,l by no possibilit stick the upper valve,since the throw o the latter is, as

has been indicated above, preferably twice as great as the throw of thelower valve.

Again, should the lower valve become` scratched by the passage of Somehard article therethrough, and thus be rendered eaky, such a particlewould not, owing to its size, in all probability, scratch the uppervalve. Such being the case, the upper va ve would operate perfectlyalone until the lower valve could be taken out and ground.

One of the important features of my invention comprises the insertionofthe web 14 between the valve seats of the two valves 6 and 12. Should.the lower valve for any reason become broken, the particles could not,owing to their size, reach the valve seat of the upper valve, owin tothe small size of the openings'provide through the web. It must beobvious that should not such a web be provided, any large Aparticle thatmight become detached from the body of the lower valve might readilysucceed iii sticking the upper valve. With the provision of theinterposed web, the efficiency of the upper valve is very markedlyincreased. In fact, the operation of repairing the lower valve might, inthe case of locomotives, be accomplished without returning thelocomotive to the round house, that is Vto say, that the pipe coupling11 with the valve12 contained therein could be taken entirely off whilethe locomotive is on the road, and the end of the injector pipe 15 beattached directly to the pipe section 8; or, in case the dama e to thelower valve is so slight that it could be repaired by the locomotive enneer, the coupling containing this vave might be unscrewed, the valverepaired by esmas him, and the coupling returned to4 the pipe withoutthe necessity of returning the engine tothe round house for re airs. Insuch an arrangement it will be o vious that a very great saving in timeand expense can be effected.

While I have described my invention as applied. articularly to a pair ofvertical c eck va ves, I do not wish it to be understood that I amnecessarily limited to valves located in this position, as m inventioncan bereadily adapted to valves ocated in other positions, and todiierent types of check valves. The improvements which I have a plied tothe valves described might readily e applied to check valves of otherkinds, that is to say, by providing the forward valve, i. e. the onenearest the outlet of the pipe, with a larger diameter and a largerthrow than the rearward valve. It is obvious also that man other changesmight be made in the detai s of the construction without departing fromthe spirit of my invention. l

What I claim and desire to secure by Letters Patent is:

1. In a device-of the character described, the combination of an inletpipe and two in dependently movable check valves contained therein, theforward valve having a larger throw or lift lthan the rearward valve.

2. In a device of the character described, the combination of an inletpi e and two independently movable check va ves contained therein, theforward valve being larger in diameter and having a larger throw or liftthan' the rearward valve.

3. In a device of the character described, the combination of an inletipe, two check valves contained therein, an a web havin restrictedopenings interposed between the valves.

4. In a device of the character described, the combination of an inletpipe, two independently movable check valves contained therein, theforward valve being larger in diameter and having a larger throw or liftthan the rearward valve, and a web having restricted openings interposedbetween the valves.

In testimony that I claim the foregoing I have hereunto set my hand.

CHARLES J.. DRURY.

Witnesses:

ZJ. R. HICKMAN, JOHN E. HALL.

